HDS Pre-commission chemical cleaning

The Issue

ProDecon received an urgent enquiry from a UK oil refinery regarding a pre-commission chemical clean on their HDS3 (Hydro-Desulphuriser). The refinery’s previous contractor had failed to manage the pH and inhibitor effectiveness of the potentially highly aggressive single stage chemistry they were using. They were stopped by the client when half the ten-year-corrosion-tolerance (6mm) in parts of the system internals had been eroded.

The refinery urgently needed to find a competent contractor to complete the works so that their flagship project did not fall any further behind and so called on the expertise of ProDecon.

The Challenge

As the previous single stage approach had been so badly applied and it was now considered by the client to be too aggressive for the circuits, ProDecon would need to look at other methods to complete the degrease, pickle and passivation chemical cleaning. It would be critical that ProDecon’s method did not cause further damage. Additionally ProDecon’s work scope was enlarged to include:

  • the SMR boiler including the
    • Steam Drum
    • Make Gas Boiler and
    • Flu Gas Boiler
  • SMR compressor pipework
  • HDS Compressor pipework
  • HDS steam generator and
  • SRU boiler and associated pipework.
  • Oxygen line from burner to filter and filter to battery limit including N2 blow dry.

The Solution

ProDecon quickly proposed a new chemical cleaning specification that was approved by the client and which would avoid any further attrition. Using ProDecon’s innovative chemistry applied in a 3 stage chemical cleaning solution our technicians were better able to monitor and control the inhibitor performance and the pH and acidity of the washes.  Also with ProDecon’s dedicated pumping units we were able to maintain the circulating velocity in the system. By the end of the project ProDecon had circulated over 3500 cubic meters of chemical cleaning solution.

Customer Benefits

  • Fast reaction to provide technical and full-service hands-on solution
  • ProDecon managed the entire administrative and physical effluent segregation, containment and disposal for the client
  • By using ProDecon’s innovative chemistry applied in a 3 stage wash the units were degreased, pickled and passivated without further loss or damage
  • ProDecon worked closely with the refinery to make sure the new specification would be effective